The Sinhalese (Sinhala: සිංහල ජාතිය Sinhala Jathiya) are an Indo Aryan ethnic group native to the island of Sri Lanka. They constitute 75% of the Sri Lankan population and number greater than 15 million. The Sinhalese identity is based on language, historical heritage and religion. The Sinhalese speak Sinhala, an Indo-Aryan language, and are predominantly Theravada Buddhists, although a small percentage of Sinhalese follow branches of Christianity. The Sinhalese are mostly found in North central, Central, South, and West Sri Lanka. According to Mahavamsa, an ancient treatise written in Pali, The Sinhalese are the descendants of the exiled Prince Vijaya who arrived from East India (today's Orissa and Bengal) to Sri Lanka in 543 BCE and early settlers from that region.